Another character could be Kakashi. As Naruto's teacher, he could play an important role in helping Naruto understand his tenketsu. He might have some knowledge or secrets about tenketsu that he imparts to Naruto. Or perhaps he has his own past experiences related to tenketsu that he shares to guide Naruto on his path.
Sasuke can also be a main focus. In a Tenketsu Naruto fanfic, Sasuke might have his own journey related to tenketsu. Maybe he discovers something about Naruto's tenketsu that makes him jealous or drives him to further his own power in a different way. Their rivalry could be intertwined with the concept of tenketsu.
Since I haven't read this particular fanfic, it's hard to say. But it could feature Naruto himself trying to deal with a new enemy who is the tenketsu destroyer. Or it might be an original character created by the fanfic writer who has this unique ability.
Naruto is often a central character in naruto exams fanfic. His journey through the exams, with his determination and growth, is a common focus. His unique skills like the shadow clone jutsu play a big role in the exam scenarios.
Sasuke is often a central character. Given his own struggle with hatred in the original Naruto series, fanfics might further explore his journey in the context of the curse of hatred, perhaps showing how he tries to overcome it in different ways.
The main character is Naruto without a doubt. But characters like Sasuke can also be important in these fanfics. Sasuke, as Naruto's rival, may be shown to have a different perspective on Naruto's past. Maybe he discovers something about Naruto's family or his own family's connection to Naruto's past that was previously unknown. And the Sannin, including Tsunade, could also be significant as they were part of the older generation with knowledge of events that could be related to Naruto's past.
Naruto himself is often a central focus. His growth as a ninja and his journey to become Hokage are popular themes to expand on in fanfic. Writers can explore different paths his life could have taken.
Huey Freeman is often a main focus. Since he's such a complex character in the original 'Boondocks', fanfic writers like to explore his thoughts and actions further. They might put him in situations that test his principles and beliefs even more.
Naruto is the central character in 'naruto dark naruto fanfiction'. But characters like Orochimaru can play a big role. He might see an opportunity in a darker Naruto and try to manipulate him for his own gain. Hinata could also be a main character in some fanfictions. Her love for Naruto might be put to the test as she tries to understand and save Naruto from his dark path. And the Sannin, especially Jiraiya, might be involved as they were important in Naruto's development in the original and could have a role in dealing with his new, darker nature.
Naruto is often a central character. Since he has such a complex personality in the original series, fanfiction writers like to explore different aspects of him in the context of duality. They might show his struggle between his role as a hero and his inner insecurities.
In addition to the main characters from the original series, some fanfictions in 'naruto paragon fanfiction' might introduce new characters. These could be characters with unique abilities or backstories that interact with Naruto and the gang. They might be from a long - lost clan or have a special connection to an ancient ninja art, which then becomes intertwined with Naruto's journey in the fanfiction.
Baby is obviously one of the main characters focused on. Fanfic writers often explore his thoughts, feelings, and his growth as a character. Debora is another main focus. Writers might write about her relationship with Baby and how she copes with the dangerous world he is involved in.